Estimate the minimum distance...

[HuguKYM]

Hi all,
I have 1 question regarding estimate distance, is there any way to estimate how much minimum distance that we need to have in order to capture object object (for example a row of 20 people) using certain focal length (example 28mm)? I just wondering because I think this is quite important (at least for me).

 

[Rashkae]

How good is your geometry and trigonometry?

 

[catchlights]

I'm not sure how I do it, once I see the size of group, I can move to a position without second thought or lift up the camera, which the widest angle of my lens able to cover.

maybe you just need more practice.

 

[zcf]

How good is your geometry and trigonometry?

http://en.wikipedia.org/wiki/Angle_of_view#Common_lens_angles_of_view

 

[Rashkae]

http://en.wikipedia.org/wiki/Angle_of_view#Common_lens_angles_of_view

Hahaha! That's cheating! They give you all the formulas!

 

[Octarine]

Hahaha! That's cheating! They give you all the formulas!

Yeah, but still some triangles to calculate in order to get the distance as asked by TS.

 

[HuguKYM]

lolz... thank you guys.. I thought there is some kind of simple ''conversion'' about this. Lolz... now i think i just calculate that... I am comfortable with mathematics afterall. Thank you all.